A known electrical junction box includes a circuit board housed in a circuit case that includes a ventilation hole. Portions of the case except for the ventilation hole are liquid-tight. According to the configuration, water resistance of the electrical junction box improves while maintaining air permeability.
Because the case described above includes the ventilation hole, foreign substances such as bugs or duct may enter into the case through the ventilation hole, which may result in malfunction of the circuit board.
The present invention was accomplished in view of the foregoing circumstances. An object of the present invention is to provide an electrical junction box that has a configuration to restrict entrance of foreign substances.